Photothermal therapy (PTT) is a minimally invasive treatment that kills cancer cells by converting photon energy into heat. The past few decades have witnessed the booming development of photothermal materials, mainly focusing on precious metal nanomaterials and carbon nanomaterials, such as nanogold and silver and nanocarbon materials for near-infrared (NIR) light-triggered PTT. As precious metals are expensive and potentially harmful to humans, exploration and development of a new type of photothermal materials has become a research hotspot in this field. Herein, we report narrow bandgap conjugated polymer nanoparticles (PDPP NPs) based on pyrrolo[3,4-c]pyrrole-1,4-dione (DPP) with intense NIR absorption at 900 nm, as well as a photothermal energy conversion efficiency of 75%. This polymer nanoparticle is essentially non-toxic, as the cell viability of mouse remained more than 90%, even when the concentration of PDPP NPs was at 0.5 mg·mL⁻¹.

光热疗法（PTT）是一种微创疗法，通过将光子能量转化为热量来杀死癌细胞。过去几十年见证了光热材料的蓬勃发展，主要集中在贵金属纳米材料和碳纳米材料上，例如用于近红外（NIR）光触发PTT的纳米金和银以及纳米碳材料。由于贵金属价格昂贵，并且可能对人体有害，因此新型光热材料的探索和开发已成为该领域的研究热点。本文中，我们报道了基于吡咯并[3,4- c的窄带隙共轭聚合物纳米颗粒（PDPP NPs）]吡咯-1,4-二酮（DPP）在900 nm处具有很强的近红外吸收，并且光热能转换效率为75％。该聚合物纳米粒子基本上无毒，因为即使PDPP NPs的浓度为0.5 mg·mL ^-1时，小鼠的细胞存活率仍超过90％。